Variation Field Map and Intraclass correlation (ICC)

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ICC models in Linear Mixed Model (LMM)

• ICC definition, ICC types (ICC(1,1), ICC(2,1), ICC(3,1)) and calculation in LMM Details: (https://github.com/TingsterX/reliability/blob/main/tutorial_ICC_in_R.ipynb)

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Theoretical Variation Field Map (3D)

• x-axis: within-individual variation
  
• y-axis: between-individual variation
• z-axis: ICC (intraclass correlation), ICC=y/(x+y)

Theoretical Individual Variation Field (2D)

• x-axis: within-individual variation
• y-axis: between-individual variation

ICC colormap:

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Example (Demo data provided in “Calculat Your Data”):

Measuring ICC and individual difference of cortical functional connectivity (seed: posterior cingulate cortex)

 

Individual variation and ICC field map: Each dot represents a brain region. Regions with higher ICC have relatively higher between-individual variation and lower within-individual variation.

 

ICC map on the cortex